Container construction



March 9, 1965 J. E; KOENIG CONTAINER CONSTRUCTION Filed Nov. 2, 1962 IN VEN TOR. JZIII/Il/ EKoen/gg BY $ma4q, 2 W

ATTORNEYS United States Patent 3,172,557 QONTAINER CQNSTRUCTION John E. Koenig, Massiilon, Ohio, assignor to The Central States Can Corporation, Massillon, Ohio, a corporation of Ohio Filed Nov. 2, 1962, Ser. No. 234,944 3 Claims. (Cl. 22054-) My invention relates to improvements in container construction, and more specifically to a container construction having a closure which may be released from the container by means of a tear strip. Even more specifically, my invention relates to a tear strip closure type of container which is particularly adapted for foods to be heated directly in the container prior to consumption.

Many prior container constructions have been provided for foods of various forms and in certain cases, it is desirable to heat these foods directly in the container immediately prior to consumption of these foods. The major problem involved in such a case is that the foods most frequently must be packed in the container so that the closure retains the contents of the container airtight. There are, of course, some foods which do not require this airtight containment, but even in those cases, the closure must be formed on the container in such a manner so as to prevent contamination and spilling of the contents from the container, thereby resulting in only a very limited, if any, air relief for the inner confines of the container.

Thus, in either case, where the contents of the container are heated directly in the container by, for instance, placing the container directly in an oven, it is necessary to provide some venting for the inner confines of the container in order to prevent a pressure build-up which otherwise would cause an accidental dislodgment of the container closure or a rupture in either the container or closure during such heating. This venting is usually accomplished by a complete removal of the container closure prior to placing the container and contents in the oven for heating, and this has resulted in the problem of part of the contents of the container boiling over or otherwise spilling from the container. Furthermore, there is the problem of contamination of the contents of the container.

It is, therefore, a general object of the present invention to provide a container construction specifically formed so that venting of the inner confines of the container may be provided for immediately prior to heating, yet the container closure will remain in place over the container during heating for preventing spilling and contamination of the contents thereof.

It is a primary object of the present invention to provide a container construction of the tear strip closure type in which a tear strip of limited peripheral length may be removed immediately prior to heating the container and the contents thereof for providing the necessary venting during such heating, yet, despite the removal of this closure partial tear strip, the closure will remain in place secured over the container open upper end.

It is a further object of the present invention to provide a container construction of the tear strip closure type and having the foregoing improved partial tear strip formed thereon which includes a permanent pull tab formed on the closure and which is not removable with the tear strip for providing ease in final removal of the closure from the container after heating.

Finally, it is an object of the present invention to provide a container construction which satisfies all of the foregoing objects in a simple and eflicient manner and may be provided at a minimum of cost.

These and other objects are accomplished by the parts, constructions, arrangements, combinations and subcombinations comprising the present invention, a preferred embodiment of which-illustrative of the best mode in which applicant has contemplated applying the principles-is set forth in the following description and illustrated in the accompanying drawings, and which is particularly and distinctly pointed out and set forth in the appended claims forming a part hereof.

In general terms, the container construction comprising the present invention for use with foods to be heated in the container prior to consumption may be stated as being of the type in which the container is preferably formed of metal, such as aluminum, and has bottom and side walls provided with flange means projecting continuously outwardly of the side walls at the upper open end of the side walls and continuously around the periphery of the container, so that this projecting flange means forms a continuous upper sealing surface and a continuous shoulder spaced below this upper sealing surface. Further, the container construction is of the type in which a metal closure, such as an aluminum closure, is provided for the container having a central closure wall terminating at its extremities in continuous outturned and then downturnedinturned flange portions continuously around the periphery of the closure, so that the closure flange portions may be engaged over, around and beneath the container flange portions and so that the downturned-inturned closure flange portion will engage the container flange means shoulder. This latter engagement will hold the closure sealed to the container with such sealing taking place between the upper surface of the container flange means and the adjacent surface of the outturned closure flange portion.

Specifically according to the improvements of the present invention, the container construction includes a continuous tear strip score line formed in the downturned-inturned closure flange portion extending continuously not greater than approximately three-quarters of the total periphery of the closure and container with a tear strip tab formed on this down-turned-inturned closure flange portion at one end portion of the tear strip score line. Further according to the improvements of the present invention, the engagement between the downturned-inturned closure flange portion and container flange means shoulder is the sole means for retaining or holding down the closure sealed on the container.

Thus, with a container construction including the improvements of the present invention, after removal of the tear strip formed by the tear strip score line, the engagement of the remainder of the doWnturned-inturned closure flange portion with the container flange means shoulder will normally retain the closure on the container'while still permitting a venting of the container in the event of a pressure build-up within the container during heating.

In the preferred form of the improvements of the present invention, the closure for the container is preferably also formed with a permanent pull tab positioned on that a part of the downturned-inturned closure flange portion at a peripheral location free of having the tear strip score line, and this permanent pull tab is also preferably positioned adjacent one end portion of the tear strip score line. Furthermore, it is preferred that the central closure wall is formed having an upturned flange portion to which the outturned closure flange portion is inwardly connected so that this upturned closure flange portion will abut the side container walls, thereby more securely normally retaining the closure positioned on the container and particularly after the partial tear strip is removed. Finally, in the preferred form, the tear strip score line in the downturnedinturned closure flange portion is limited'to not greater than approximately one-half the total closure and container periphery, again for the more secure retainrnent of the closure on the container after removal of the partial tear strip.

By way of example, an embodiment of the container construction of the present invention is illustrated in the accompanying drawings forming a part hereof, wherein like numerals indicate similar parts throughout the several views, and in which:

FIG. 1 is a side elevation of a container including the improvements of the present invention;

FIG. 2, an enlarged fragmentary sectional view, part in elevation, looking in the direction of the arrows 22 in FIG. 1;

FIG. 3, an enlarged fragmentary sectional view, part in elevation, looking in the direction of the arrows 3-3 in FIG. 1;

FIG. 4, a fragmentary side-top perspective-view'showing the partial tear strip of the present invention being removed from the closure;

FIG. 5, an enlarged fragmentary sectional view, part in elevation, looking in the direction of the arrows 55 in FIG. 4; 7

FIG. 6,a perspective view similar to FIG. 4, but with the partial tear strip completely removed and the closure partially disengaged from the container;

FIG. 7, an enlarged sectionalview, part in elevation, looking in the direction of the arrows 77 in FIG. 4,'Wit.l1 the tear strip score line extending-slightly less than approximately one-half of the total periphery of the closure and container and with the tear strip removed; and

FIG. 8, a view similar to FIG. 7, but with' the tear strip score line extending slightly less than approximately threequarters of the total periphery of the closure and container.

Referring to the drawings, the container construction of the. present invention includes the container, generallyindicated at 10, having the usual bottom wall 11 and side walls 12, with the side walls terminating upwardly in a preferably outwardly rolled or outwardly beaded edge 13 extending continuously around the periphery of'the container and forming an upper open end 14. The container 'is preferably formed of metal, such as aluminum or tinplate, although other materials capable of withstanding heat might be used, and the heading of the upper edge 13 forms this edge with an inner, generally vertically extending wall surface 15 terminating upwardly in an arcuate upper sealing surface 16. Furthermore, the'upper sealing surface 16 terminates outwardly in an arcuately downwardly-inwardly extending outer flange portion 17 which forms the continuous shoulder 18 spaced below the upper sealing surface 16.

A closure, generally indicated at 19, is provided for the container 10 and is also preferablyforrned of metal, such as aluminum. The closure 19 is formed with the disc-like central closure wall 20 which terminates outwardly at its extremities in a continuous edge portion formed preferably'first in a generally vertically upwardly extending flange 21 substantially matching the inner wall surface 15 of the container 19, and then in a continous outturned preferably arcuate flange portion 22 conforming generally to the upper sealing surface'16 of container 10, and then in a continuous preferably arcuate downturned-inturned flange portion 23 substantially matching the outer flange portion 17 of the container 10.

In the case where the container 10 is to be sealed airtight or at least liquid-tight by the closure 19, a plastisol gasket sealing compound 24, may be provided on the inner surface of the outturned flange portion 22 of the closure 19, as shown in FIGS. 2 and 3. Furthermore, dependent on the particular foods to be placed within the container 19, the innerrsurfaces of the container 10 and closure may be provided with usual thin plastic coatings.

Thus, the closure 19 may be received positioned over the container upper open end 14 with the closure central closure wall 29 extending within the container side Walls 12, the closure vertical flange portion 21 inwardly abutting the container inner wall surface 15, the closure outturned flange portion 22 overlying and sealing against the container upper sealing surface 16, with the gasket sealing compound 24 therebetween when provided, and finally, the closure downturned-inturned flange portion 23 engaged downwardly .around the container outer flange portion 17 and engaging beneath the container shoulder 18. This engagement of the closure downturnedinturned flange portion 23 with and beneath the container shoulder 18 will normally securely retain the closure 19 sealed over the upper open end 14 of container 10.

According'to the improvements of the present invention, a tear strip score line 25 is formed preferably at the inner surface in .the closure downturned-inturned flange, portion 23, preferably about at the point of joinder of this downturned-inturned flange portion 23 with the closure outturned .flange portion 22, but in any event, above the container shoulder 18 as determined when'the closure .19 is sealed over the upper open end 14 of container 10, for instance, as best seen in FIG. 3. This tear strip score line 25 at its extreme end portions extends downwardly to the lower free edge of the closure downturned-inturned flange portion 23 in the usual manner for ease in beginning and terminating the tearing operation, and the complete removal of the tear strip, as shown, but most important according to the principles of the present invention, this tear strip score line 25 extends around the periphery of the closure 19 and the container upper open end 14 not greater than approximately or substantially three-quarters of the total periphery, and in the preferred form, for most uses, not greater than approximately or substantially one-half the total periphery.

Furthermore, a tear strip tab 26 isformed on the closure downurned-inturned flange portion 23 at one of the extremities or end portions of the tear strip score line 25 and normally extending downwardly from this closure flange portion 23 along the outer surface of the container side walls 12. Also, a permanent normally downwardly extending pull tab '27 is formed on the closure 19 extending downwardly from the closure downturned-inturned flange portion 23 at a peripheral location on this flange portion free of containing or having formed therein the tear strip score line 25. It is preferred that this permanent pull tab 27 will be positioned adjacent one of the end portions of the tear strip score line 25 .as .shown, for instance, in FIG. 1.

In use of the container construction including the improvements of the present invention, a feed to be heated in the container 10 prior to consumption is placed therein and the closure 19 sealed over the upper open end 14 of the container, that is, with the closure vertical flange portion 21 abutting the container inner wall surface 15, the closure outturned flange portion 22 sealing against the container upper sealing surface 16, and the closure downturned-inturned flange portion 23 engaged downwardly beneath the container shoulder 18. When it is desired to heat the food contents of the container 10, the tear strip tab 26 is grasped and pulled upwardly and then sideways in the direction along the tear strip score line 25, thereby removing the tear strip 28 formed by that portion of the closure downturned-inturned flange portion 23 below the tear strip score line 25.

This tear strip 28, as determined by the peripheral extent of the tear strip score line 25, will extend preferably not greater than approximately one-half of the total periphery of the closure 19 and container 10, although under certain conditions, dependent on the food contained in the container and the particular thickness and temper of the metal forming the closure 19, this tear strip 28 can extend to not greater than approximately three-quarters of the total periphery of the closure 19 and container 10. The important point is, when the tear strip 28 is removed along the tear strip score line 25, a permanent part 29 of the closure downturned-inturned flange portion 23 remains still engaging the container shoulder 18 and retaining the closure 19 on the container 10. Furthermore, this permanent part 29 of the closure downturned-inturned flange portion 23 includes the closure permanent pull tab 27.

Thus, the container 10 having the partially released closure 19 and containing the food to be heated may then be inserted directly into an oven and during heating, any pressure build-up within the container 10 is immediately released over the container upper sealing surface 16 along the peripheral location where the tear strip 28 has been removed from the closure 19. Since the tear strip 28 has been removed, at this peripheral location the closure 19 is not engaged with the container shoulder 18 and any slight build-up of pressure automatically raises the closure at this location a small amount merely sufficient to relieve this pressure. At the same time, however, the permanent part 29 of the closure downturnedinturned flange portion 23 which is still engaged with the container shoulder 18 will retain the closure 19 secured on the container 10.

Furthermore, the formation of the closure 19 with the vertical flange portion 21 which normally engages within the container inner wall surface 15, will aid the permanent part 29 of the closure downturned-inturned flange portion 23 in the retaining of the closure 19 on the container 10 despite the partial tear strip 28 having been removed since this fiange portion retains the closure against horizontal shifting relative to the container. Also, after the food within the container 10 has been heated as desired, the permanent pull tab 27 may be grasped for the final complete removal of the closure 19 from the container 10, and this removal operation will require the least upward force when this permanent pull tab 27 is positioned adjacent one of the end portions of the tear strip score line 25 due to somewhat of a peeling action taking place.

This final removal of the closure 19 from the container 10 is illustrated in FIG. 6 and, as shown, for maximum ease, will begin along the peripheral portion of the closure 19 where the tear strip 28 has been removed. Furthermore, the container construction is illustrated in FIG. 7 with the tear strip 28 removed and with the tear strip score line 25 extending slightly less than onehalf the total periphery of the closure 19, whereas in FIG. 8, the container construction is illustrated with the tear strip 28 removed and the tear strip score line 25 extending slightly less than three-quarters of the total periphery of the closure 19.

Thus, according to the principles of the present invention, a container construction is provided in which a partial tear strip 28 may be removed so that food may be heated directly in the container 10 with the closure 19 partially secured on the container yet the container is automatically vented during such heating.

Furthermore, in view of the fact that the closure 19 is still retained on the container 10 during this heating, made possible by this automatic venting, the food within the container being heated is protected against overflow, spilling and contamination.

Finally, after the food contents of the container 10 has been heated as desired, the closure 19 may be completely removed without difliculty by use of the permanent pull tab 27 and despite the fact that the container will be warm and must be handled using protection against heat.

It is pointed out that various food products to be heated prior to consumption may be packaged in the container construction of the present invention and where these food products are liquids or it is otherwise desired to provide an airtight seal prior to heating and use, the gasket sealing compound 24 may be used between the closure '19 and container 10. There are occasions, however, when a complete airtight seal may not be required for containing various forms of foods, such as some in a dry state, and in such event, this gasket sealing compound may not be required and the seal between the closure and container might not be airtight. It should be understood however, that all such conditions are fully contemplated within the principles of the present invention.

In the foregoing description, certain term have been used for brevity, clearness and understanding but no unnecessary limitations are to be implied therefrom, because such words are used for descriptive purposes herein and are intended to be broadly construed.

Moreover, the embodiment of the improved construction illustrated and described herein is by way of example and the scope of the present invention is not limited to the exact details of construction shown.

Having now described the invention, the construction, operation and use of the preferred embodiment thereof, and the advantageous new and useful results obtained thereby, the new and useful construction and reasonable mechanical equivalents thereof obvious to those skilled in the art are set forth in the appended claims.

I claim:

1. In container construction for foods to be heated in the container prior to consumption of the type in which a container having bottom and side walls is provided with an outwardly extending bead at and continuously around an upper open end of the side walls forming an outwardly projecting shoulder at the underside of said bead; and in which a metal closure is positioned with a central closure wall recessed downwardly within the container upper open end and inwardly adjacent the container bead, and a continuous edge portion engaged with inner surfaces of the container side Walls inwardly adjacent the container bead and extending upwardly over and around the container bead and having an outer part extending downwardly and engaging beneath the container bead shoulder; the improvements including a tear strip score line formed in the outer part of the closure edge portion located above the container bead shoulder and extending continuously at least substantially one-half and not greater than substantially three-quarters of the total periphery of the metal closure and container forming a tear strip, a tear strip tab formed on the closure edge portion at one end and as part of the tear strip, the score line at the other end of the tear strip extending to a free edge of the closure forming the tear strip completely removable from the closure, and the engagement between the remainder of the closure edge portion and the container bead shoulder in cooperation with the engagement between the closure edge portion and the container side wall inner surfaces normally holding the closure on the container after the complete removal of the tear strip with said flange portion engagements being the sole means for accomplishing said holding; whereby, after the complete removal of the tear strip, the engagement between the remainder of the closure edge portion and the container bead shoulder in cooperation with the engagement between the closure edge portion and the container side wall inner surfaces will normally hold the closure on the container while still permitting a venting of the con- 7 tainer in the event of a pressure build-up within the container during heating, and after-heating, an upward 'force on the closure will completely removethe closure free of the container.

2. Container constructionas defined in claim 1 in which a permanent pull tab isrformed on the outer part of the closure edge portion at 1a vperipheral location free of having the tear strip score line suchthat the complete removal force can be applied to the'closure throughsaid permanent pull tab after heating.

-3. Container construction as :defined in claim 1 in which the tear strip score line'is formed in .the outer part of the closure edge portion'located above the container bead shoulder extending continuously substantially one-half of the total periphery of the metal closure and container forming said-tear strip.

References Cited in the file of this. patent UNITED STATES PATENTS 

1. IN CONTAINER CONSTRUCTION FOR FOODS TO BE HEATED IN THE CONTAINER PRIOR TO CONSUMPTION OF THE TYPE IN WHICH A CONTAINER HAVING BOTTOM AND SIDE WALLS IS PROVIDED WITH AN OUTWARDLY EXTENDING BEAD AT AND CONTINUOUSLY AROUND AN UPPER OPEN END OF THE SIDE WALLS FORMING AN OUTWARDLY PROJECTING SHOULDER AT THE UNDERSIDE SAID BEAD; AND IN WHICH A METAL CLOSURE IS POSITIONED WITH A CENTRAL CLOSURE WALL RECESSED DOWNWARDLY WITHIN THE CONTAINER UPPER OPEN END AND INWARDLY ADJACENT THE CONTAINER BEAD, AND A CONTINUOUS EDGE PORTION ENGAGES WITH INNER SURFACES OF THE CONTAINER SIDE WALLS INWARDLY ADJACENT THE CONTAINER BEAD AND EXTENDING UPWARDLY OVER AND AROUND THE CONTAINER BEAD AND HAVING AN OUTER PART EXTENDING DOWNWARDLY AND ENGAGING BENEATH THE CONTAINER BEAD SHOULDER; THE IMPROVEMENTS INCLUDING A TEAR STRIP SCORE LINE FORMED IN THE OUTER PART OF THE CLOSURE EDGE PORTION LOCATED ABOVE THE CONTAINER BEAD SHOULDER AND EXTENDING CONTINUOUSLY AT LEAST SUBSTANTIALLY ONE-HALF AND NOT GREATER THAN SUBSTANTIALLY THREE-QUARTERS OF THE TOTAL PERIPHERY FO THE METAL CLOSURE AND CONTAINER FORMING A TEAR STRIP, A TEAR STRIP TAB FORMED ON THE CLOSURE EDGE PORTION AT ONE END AND AS PART OF THE TEAR STRIP COMPLETELY REMOVABLE OTHER END OF THE TEAR STRIP,EXTENDING TO A FREE EDGE OF THE CLOSURE FORMING THE TEAR STRIP COMPLETELY REMOVABLE FROM THE CLOSURE, AND THE ENGAGMENT BETWEEN THE REMAINDER OF THE CLOSURE EDGE PORTION AND THE CONTAINER BEAD SHOULDER IN COOPERATION WITH THE ENGAGEMENT BETWEEN THE CLOSURE EDGE PORTION AND THE CONTAINER SIDE WALL INNER SURFACES NORMALLY HOLDING THE CLOSURE ON THE CONTAINER AFTER THE COMPLETE REMOVAL OF THE TEAR STRIP WITH SAID FLANGE PORTION ENGAGEMENTS BEING THE SOLE MEANS FOR ACCOMPLISHING SAID HOLDING; WHEREBY, AFTER THE COMPLETE REMOVAL OF THE TEAR STRIP, THE ENGAGEMENT BETWEEN THE REMAINDER OF THE CLOSURE EDGE PORTION AND THE CONTAINER BEAD SHOULDER IN COOPERATION WITH THE ENGAGEMENT BETWEEN THE CLOSURE EDGE PORTION AND THE CONTAINER SIDE WALL INNER SURFACES WILL NORMALLY HOLD THE CLOSURE ON THE CONTAINER WHILE STILL PERMITTING A VENTING OF THE CONTAINER IN THE EVENT OF A PRESSURE BUILD-UP WITHIN THE CONTAINER DURING HEATING, AND AFTER HEATING, AN UPWARD FORCE ON THE CLOSURE WILL COMPLETELY REMOVE THE CLOSURE FREE OF THE CONTAINER. 